The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2001-185578 filed on Jun. 19, 2001 the entire contents thereof is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a wheel structure for further enhancing the rigidity of the wheel.
2. Description of Background Art
A wheel structure of a vehicle, particularly an all-terrain vehicle, is set forth, for example, in Japanese Utility Model Publication No. Sho 62-71003, entitled xe2x80x9cMinor-Diameter and Wide Wheel.xe2x80x9d
In FIGS. 1 and 2 of the above-mentioned publication, the minor-diameter and wide wheel in which discs 15a, 15b which are the respective bottoms of two cup-shaped rim halves 2A, 2B (characters and reference numbers used in the publication are used as they are) are united with the edges of these rim halves 2A, 2B, respectively, curled in the reverse shape of a U and with ears 11a, 11b being formed.
The minor-diameter and wide wheel is a wheel wherein the width, that is, the rim width of which (the distance between the inner surface 23 of the ear 11a and the inner surface 23 of the ear 11b) is large, compared with the diameter, for example, the outside diameters of beads 12a, 12b. 
For such a wheel, it is estimated that when external force acts upon the wheel from a tire, the flexure of the side of each ear 11a, 11b becomes larger, compared with the flexure of the side of each disc 15a, 15b because the distance from each disc 15a, 15b, respectively, attached to the side of a vehicle body to each bead 12a, 12b for holding a tire is large. Therefore, it is desirable that the rigidity of the side of the ears 11a, 11b is higher. However, in the case where the rim halves 2A, 2B are thickened to enhance the rigidity, the weight is increased.
It is an object of the present invention to provide a wheel structure wherein the rigidity of the wheel is enhanced without increasing the weight.
To achieve the object of the present invention a wheel is formed with a disc and a rim wherein a larger-diameter part, the diameter of which is larger than the diameter in the center, is provided at the edge of the rim via a part having a difference in a level. A curled part is provided on both edges of the rim by curling the larger-diameter part. The end of the curled part is in contact with the part having a difference in a level.
The part having a difference in a level is provided to the rim wherein the rigidity of the side of the edge of the rim can be enhanced. As a result, the rigidity of the whole wheel can be more enhanced.
The present invention includes a protrusion that is formed for reinforcement that protrudes inside a curled part.
As the protrusion for reinforcement is formed, the rigidity of a wheel can be more enhanced by a part having a difference in a level and a protrusion.
The present invention is based upon a wheel formed by a disc and a rim and includes a protrusion for reinforcement that is formed at both edges of a rim and a curled part that is formed at the edges.
As the protrusion for reinforcement is formed in the rim, the rigidity of both edges of the rim can be enhanced by a simple structure and as a result, the rigidity of the whole wheel can be enhanced.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.